Dissapointing inhumane service by FNB

I have an account with thia bank for over 20 years,I usually swipe my account at tollgates and for some reasons unknown to me tjey don't deduct these sanral fees on the same day and the day they get deducted is when I no longer have money in my bank account.Then instead of leaving the account there on a minus or rather block transactions if a person doesn't have money,FNB chose to wrip me off and charged me R450,R430,R350 in unpaid funds, as at today my account is on -R1678.00

FNB what kind of a w******* is this,Sanral system doesn't deduct money on time and I get punished for tha,charging a person over R400 for unpaid funds, instead of assisting your cunsumers you put them more and more into debt and distress. Is this even allowed by consumer protection act ? I hate this bank and my loyalty for you has never assisted me with anything instead what you do is put your customers into distress, where should I get this money from, you act like you are the unregistered loan sharks, even worse than them.